Human interface rotor system helicopter (HIR)

ABSTRACT

A single place helicopter comprising a lower airframe and an upper airframe, having a rotor shaft attached thereto, rotor blades, and a hub on said rotor shaft with means to change blade pitch for vertical flight. The upper airframe comprising a rotor system, engine, tail boom and tail rotor tilt as one unit with the pilot forward, rearward and in a lateral attitude for directional flight control by means of a hinged gimbal joint or block fastened between the vertical tubes on the lower airframe that connect the upper and lower airframes. By allowing the pilot to move with the rotor system, this configuration combines weight and CG manipulation in a tilt rotor design that eliminates the angular differences between advancing and retreating rotor blades during lateral flight and allows for a simplified human interface flight control system in a single-main-tilt rotor helicopter.

This invention relates to rotary-winged aircraft and in particular to such aircraft that are of a single mast tilt rotor design. There is a need for helicopters and rotorcraft in general to utilize rotor systems that allow rotorcraft to be flown more easily, have fewer moving parts with a longer wear life and less expensive maintenance costs. Such aircraft would be easier to train others to operate. One concept of thinking that has not been addressed is the combination of human interface, ie the pilot moving with the machine, center of gravity manipulation and CG shift and a single mast tilt-rotor concept. The object of the present invention is not to combine the aerodynamics of both fixed and rotor wing to attain what the V22 Osprey concept already achieves, but rather a combination of human interface/CG shift combined with a tilt rotor design for a more efficient single rotor helicopter.

SUMMARY OF INVENTION

One of the principal objects of this invention is to provide a helicopter that is easier to train to operate and maintain. A further object of this invention is to provide a single mast tilt rotor helicopter that utilizes two seperate airframes joined by a gimbal block or joint for tilting of the rotor system for directional flight control. A still further object of this invention is to provide a helicopter that utilizes human interface weight shifting and CG shift for assisted tilting of the rotor system. The tilt rotor design of the present invention is not restricted to the tilting of a pylon, split-mast rotor or even tilting the transmission and power plant, but rather a single mast tilt rotor in which the complete rotor system, drive train, power plant and a portion of the airframe, to include the tail boom, all tilt in unison with the operator for directional flight control. This is achieved by redesigning the airframe so that there are two seperate structures joined with a gimbal joint or gimbal block. In this configuration the airframe is gimbaled and the pilot sits in a seat that is primarily fixed to the lower airframe by the use of a spherical bearing. The forward portion of the seat, under the pilot's legs, attaches to two extending struts by support control rods. These two struts attach to the upper airframe. The lower airframe consists of the landing wheels and two static masts or vertical down tubes, canted rearward about 20 degrees and are supported by two smaller support braces that form a type of semi-tripod braced airframe. Located'at the top of the down tubes is the required gimbal joint or fastened mid-way up the down tubes, just behind the pilot's seat, is a gimbal block. Which ever connecting unit is used, gimbal joint or gimbal block, the purpose of either joint is to connect the upper airframe to the lower airframe. The upper airframe is comprised of the complete rotor system, reduction drive, power plant, tail boom and the above mentioned extending struts that extend down through and between the vertical down tubes and lateral support braces and continue under the pilot's seat, parallel with the pilot's legs, supporting the tail rotor pedals at the pilot's feet. These two struts have a limited range of motion to the left, right, up and down. Where the left strut fastens just below the power plant frame is the portion of the upper airframe to which the collective pitch stick is located, canted 40 to 45 degrees toward and across the left leg of the pilot. This prevents unwanted change of the collective pitch of the rotor blades during forward and aft flight. When the pilot pushes the cyclic stick forward the pilots seat and above mentioned portions of the helicopter move only slightly with the rotor system. Most of the pilot's weight is supported on the lower airframe. Aside from being an efficient method for rotor disc control, the present invention is an improved helicopter over helicopters of the prior art by utilizing a rotor system with fewer moving parts. A thrust bearing plate assembly is used to control collective pitch, replacing the existing complicated swash plates used in helicopters today.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of the testing prototype helicopter with no gimbal block or joint, only a single tilting axis for forward and aft test flight to prove the concept of human interface in single mast tilt rotors.

FIG. 2 is a perspective view of the gimbal joint configuration helicopter with the gimbal joint fastened atop the dual vertical down tubes.

FIG. 3 is a perspective view of the gimbal block version helicopter with the gimbal block fastened in the center and between the vertical down tubes just behind the pilot's seat.

FIG. 4 depicts the lower airframe with the gimbal block configuration fastened in the center of the vertical tubes.

FIG. 5 shows an enlarged view of the gimbal bock with lateral axis pin recepticle and forward/aft axis pin.

FIG. 6 is a perspective view of the lower airframe with a gimbal joint at the top of the vertical tubes rather than the gimbal block in the center of the vertical tubes as depicted in FIG. 4.

FIG. 6A is a perspective view of a gimbal joint rather than the gimbal block.

FIG. 7 depicts an enlarged view of the tilting mechanism/pylon inverted to show detail of the vibration resistent guide wheels and the lateral tilting plate with the stainless steel single slide/lateral tilting axis rod.

FIG. 7A depicts the tilting mechanism/pylon right side up

FIG. 8 is a perspective view of the tilting mechanism/pylon assembled to the lateral tilting plate by means of spacing blocks and the stainless steel slide/lateral tilting axis rod.

FIG. 9 is a detailed view of the lower airframe in the gimbal block configuration with one vertical down tube cut away to show detail of the flight control linkages attached to the tilting mechanism and lateral tilting plate.

FIG. 10 is a perspective seperated view of the lower and upper airframes for the gimbal block configuration and general view of a portion of the rotor system.

FIG. 10A is a side view of the lower airframe to show the placement of the spherical bearing of the pilot's seat.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Refering now to the drawings in FIGS. 1, 2 and 3 in more detail, the helicopter of this invention is generally designated by reference numeral 70. The helicopter of the present invention can be assembled into one of three different configurations. The first being a testing configuration, FIG. 1, having only a single tilting axis forward and aft with tail rotor yaw control. The second configuration, FIG. 2, has a gimbal joint at the top of the vertical down tubes from which the upper airframe is manipulated resulting in tilting of the said upper airframe forward, aft and in lateral directions for directional flight control. The third configuration, FIG. 3, has a gimbal block fastened in the center and between the vertical down tubes. For the purpose of the detailed drawings of the present invention the depicted helicopter will be the third configuration, FIG. 3 with the gimbal block.

As shown in FIG. 4, the lower airframe 1 is configured in a semi-tripod style with two vertical down tubes 8, lateral support braces 9, a pilot's seat 5 and a gimbal block 2. As shown in FIG. 5, the gimbal block 2 consists of two axises of movement. A forward/aft axis pin 3 fastens the gimbal block to the lower airframe between the vertical down tubes midway up the said down tubes. The lateral axis pin recepticle 4 with bronze bearing attaches the upper airframe 22 to the gimbal block 2 by means of a lateral axis pin 23 shown clearly in FIG. 10.

As clearly shown in FIGS. 6 and 6A the lower airframe 1 is an alternate airframe with a gimbal joint fixed at the top portion of the vertical down tubes 8. This type of helicopter is clearly illustrated in FIG. 2.

As shown in FIGS. 7, 7A and 8, the rotor tilt mechanism 9 contains two vibration resistent wheels 12 that guide the tilting mechanism 9 as it traverses forward and rearward along an axis utilizing a bronze bearing 11 through which an axis of stainless steel 14 guides the tilting mechanism forward and rearward, tilting the upper airframe 22 in like manner for forward and aft flight. The tilting mechanism attaches to a lateral tilting plate 13.

The stainless steel slide axis 14 also functions as a lateral tilting axis for the tilting mechanism 9.

As shown in FIG. 9, the control stick 21 operated by a pilot, tilts the upper airframe 22 and rotor system through a system of bell cranks 15 and push/pull connecting rods 20 that slide the tilt mechanism 9 that is attached to the upper airframe by means of a spherical bearing 10 forward and aft and tilts the lateral tilting plate 13 laterally for directional flight control and thereby allowing the pilot seat 5 to tilt in like manner with the upper airframe 22 as it is mounted in line with the gimbal block 2. Moving the control stick 21 to the right will tilt the tilting plate yoke 17 and lateral tilting plate 13 to the right and thereby tilting the rotor system and upper airframe left, causing the helicopter to fly left in a lateral manner. The complete assembly consisting of the tilting mechanism 9 and the lateral tilting plate 13 attach to the lower airframe 1 by means of two bearing blocks 18 and facilitate tilting of the of the rotor assembly in lateral directions. A single place helicopter as seen in FIG. 10, comprising a fuselage that consists of a lower airframe 1 and an upper airframe 22; having a rotor shaft 31 attached thereto, rotor blades, and a hub on the shaft with means on said rotor shaft consisting of a thrust bearing assembly to change the blade pitch in a collective manner for vertical flight. The upper airframe 22 comprising the main rotor system, engine 30, drive train, tail boom 28 and tail rotor 29 tilt as one unit forward, rearward, left, and right for directional flight by means of a gimbal block 2 fastened to the lower airframe 1 between the two vertical down tubes 8 just behind the pilot's seat 5, connecting the upper and lower airframes. The vertical tubes 8 of the lower air frame 1 cant to the rear so as to allow a sliding tilt mechanism 9, as seen in FIG. 8, to traverse forward and rearward, thereby tilting the upper airframe 22 and rotor system from the lower portion of the upper airframe 26. As depicted in FIG. 10, this rearward cant of the down tubes 8 also allows freedom of movement for said lower portion of the upper airframe 26 to move forward, rearward and in lateral directions above and within the lower airframe main center support beam, vertical down tubes 8 and lateral support braces 9 without pushing the center of gravity outside the safe operating range of the aircraft. As shown in FIGS. 10 and 10A, a pilot's seat 5 is attached to both the vertical down tubes 8 of the lower airframe 1 at the upper portion of the seat by means of a spherical bearing 32, more clearly seen in FIG. 10A, and to the upper airframe 22 at the lower end of the seat 5 by means of two control rods 7 that attach to two struts 25 fastened in a rigid manner to the upper airframe 22 that extend down through from the upper airframe 22 to the lower airframe 1, stopping just under and slightly forward of the pilot's seat 5. At the end of said struts 25 is located the tail rotor control pedals 24. This configuration distributes the weight of the pilot between both the upper and lower airframes as the pilot's seat 5 is attached to both and moves with the upper airframe 22 thereby changing the thrust vector of the rotor blades and slightly shifting the CG or center of gravity of the helicopter for directional flight control. By allowing the pilot's seat to move with the upper airframe this causes a shift in the pilot's body weight and thereby culminating the means of weight and center of gravity manipulation in a tilt rotor design into the most versatile tilt rotor helicopter that utilizes fewer parts with longer part life and reducing maintenance costs. The helicopter of the present invention would be easier to operate with less manipulation of flight controls as the elimination of the swash plate negates the angular differences between the advancing rotor blade and retreating rotor blade. This should allow an average person to learn the operation of the aircraft with minimal training.

REFERENCES CITED

-   U.S. Pat. No. 2,352,342 PITCAIRN -   U.S. Pat. No. 3,118,504 CRESAP (BELL AEROSPACE ASSIGNOR) -   U.S. Pat. No. 3,391,746 CARDOSO -   U.S. Pat. No. 3,586,263 PAYNE -   U.S. Pat. No. 3,765,622 HAINES -   U.S. Pat. No. 3,921,939 GARFINKLE -   U.S. Pat. No. 4,071,206 MAGILL -   U.S. Pat. No. 4,473,199 MAGILL -   U.S. Pat. No. 5,370,341 LEON -   U.S. Pat. No. 5,740,987 MORRIS et al. -   U.S. Pat. No. 6,293,492 B2 YANAGISAWA -   U.S. Pat. No. 7,128,293 B2 ISLEY -   U.S. Pat. No. 7,168,656 B2 PAI -   U.S. Pat. No. 7,198,223 B2 PHELPS III. 

1. A light helicopter that utilizes a gimbaled airframe in conjunction with weight and CG manipulation for directional flight control.
 2. A single-main-tilt rotor helicopter wherein the complete rotor system, upper airframe, power plant, pilot's seat, tail boom and tail rotor tilt as one unit resulting in manipulation of the rotor disc in like manner for directional flight control by means of human interface or allowing the pilot to move with the rotor system.
 3. A single-main-tilt-rotor helicopter wherein the differences between the angles of attack of the advancing and retreating blades are eliminated as the swash plate has been replaced with a thrust bearing assembly. The amount of flight control input when maneuvering the aircraft from a hover into lateral flight is reduced as the complete rotor system and upper airframe tilt in unison in a lateral manner with out the use of a swash plate.
 4. A single-main-tilt rotor helicopter that utilizes fewer parts for rotor control and thereby allowing for a decrease in the rate of ware on parts that are utilized and by so doing extending the duration of operational hours for required parts which in turn lowers maintenance costs. 